I've been renovating a lot of default EA lots lately, and I keep running into the same sort of problem on different lots... fences and stairs that can't be cloned or CASTed. I need to move a staircase or fence section, or want to build a new one that matches the pre-existing style. But the EA versions refuse to clone ("nothing here can be cloned"). And while I can create new ones, it won't let me apply the style of the pre-existing ones to the new one, says the old one can't be designed and won't open the CAST tool.
On a couple of occasions, I've gone so far as to place a new fence alongside the old one, and tediously go through every single wood texture to find the one that has the same wood grain pattern, only to find that none of them do. So I suspect it's because the EA builders did something with the textures that we're not allowed to. But is there any way of solving this, other than giving up on the original style and making do with something similar but not quite right?
Sometimes it is just easier to delete and redo rather than try to recolor these items. I do that all the time. And some EA things will not CASt. There are some fences I have that are CC versions of some of them and they can CASt. So I just use them.
Some of the Sunset Valley lots used assets that weren't available in the finished game, such as textures and railings. Those are unCAStable because the CASt data does not exist in the game files any more. In fact, we had some quite strange glitches caused by these textures early on in the game's history! So perhaps these are the items you have found.
Well, feh. Not the answer I wanted, but not too surprising either. I LIKE some of these original textures and would rather not change them, but if I can't match the new pieces, I suppose I'll have to. I do make it a point when renovating not to allow myself any changes that real people living there wouldn't consider reasonable under real-world limitations. And it IS a real-world problem that if you're dealing with an old house, you might not be able to get new materials that look exactly the same. So I suppose I shouldn't complain. But still, feh.
Hmm. It's apparently not just EA default lots. The other day I accidentally dragged a padsttern meant to go elsewhere onto a stair railing, making it look like a pretzel stick. Momentarily amusing, but not the look I was going for. And the game wouldn't let me fix it, just insisted that the stair railing wasn't stylable. The only way I could fix it was by destroying the entire staircase and replacing it from scratch -- which wasn't fun, given that the rest of the house was already built around the staircase. Through trial and error, I discovered it would let me restyle the railing only within the first few moments after the stair was placed -- I think before switching out of build mode, though I was too frustrated to test that far. But any time I tried to come back to it later, the railing would be unstylable.